Once you finish all of your second story additions, I would landscape the garden. Put a garden with taller plants in front of the two front windows, those windows are so out of proportion with the rest of the facade, put garden beds against the screening wall etc etc. install your timber decking along the front adding planters for more plants.
What is the correct colour of the bricks, pictures are not the same colour brick. The light garage door looks good, maybe change out the window frames to the same colour.

I wouldn’t touch the brick except maybe the blade column to make it more of a feature. I don’t like the dark windows, the white door frame looks better IMO breaking up the sea of bricks.
Darken the down pipes a bit and increase density of planting in front of walls. Tidy up the timber pergola, increase size of landing if you want. Add a tree to front yard.

Are the 2 photos from different times ? The lower , clearer picture logically would be the 'later' picture , but confusingly for me , it doesn't seem to have what I assume you call a 'screen wall' -- it appears to have a pergoda type roof ? So I assume the first picture is actually some years later than the lower one ?

And being point blank -- that side of the house is plain / boring , but I'll get to that soon .

You say about a front deck -- where and why ? IF you were going to do one , where that pergoda is would be the logical place , but hello -- you have the pergoda there , with a 'screen' ( solid looking wall ) which is presumably suitable for seating , offers privacy , maybe has a clear roof or similar . If the beach is to the rear , the back yard is more private ( even if you don't have a sea view at ground level ) -- why sit out the front , in what will still be a plain/boring facade ?

Now I have mentioned it is plain IMO , so what to do ? Personally , i think you have missed the obvious -- that roof screams '80's in Mission Brown . No matter what else you do , the roof will detract . Yes -- the main problem in my eyes is the roof !

Now , assuming my guess that Pic 1 is actually the house now is correct , the gardens are looking better , the pergoda roof adds interest , the brick is pleasant , and rendering will simply turn it from a plain brick house , into a plain rendered house with an 80's roof .

So paint ( or change ) the roof to your favoured monument , do the pergoda also in monument so it looks tied in together , do all the trim in crisp white , leave the bricks as bricks ( doing some render panels will simply make it look like you are trying to hide the 80's , which ironically will highlight it , so embrace it ) , and stand back -- you are almost done !

IF I have assumed incorrectly , and Pic 2 is the current , then thats easy too -- plant some plants to hide the plainer walls , do a screen wall and pergoda , then carry on as above .

I agree that roof colour needs addressing. The other issues for me are the down pipe which appears to split your house in half and then there is the issue of a lack of obvious entry. Sort these things out first with landscaping and you'll be well on your way.

If budget is an issue (and really that’s all of us, unless we’re on a television show 😉) and you’re planning an extension, I’d stick to a bit of trim paint and some landscaping at least until you have the plans in place. Any second floor extension will change the roofline profile and that alone will impact the aesthetic. It’s way more cost effective, and generally more successful, to have a whole house design plan than make changes piecemeal. Very much envy you your view. Much as I’m enjoying country living, I do miss my sea views

There is great opportunity here for your garden to really soften and complement your home! I love the open lawn that flows out to the kerb (without a footpath in the way) so I would definitely keep any planting closer to the house and leave it open.

I am guessing the second photo is more recent, which is a shame as I really like the timber pergola and feel that is a great feature of the facade. This gives the brick wing wall purpose and also conceals what is probably a bathroom window (the glass bricks).

If your budget permitted, I would definitely look to reinstate the pergola.

The trees look like FIgs and are quite dated, so I would remove those and start fresh with all new planting. Choose a planting theme that you like and go with it! It sounds like you are coastal, so there are a couple of palettes that would work really well.

You could chose a great range of native grasses and flaxes to provide some wonderful contrasts in foliage textures. Masses of soft native grasses along the base of the brickwork would look great.

Otherwise a tropical palette would also work. Go for a couple of feature dwarf palms, Birds of Paradise (smaller variety) and even some colourful Cordylines.

Then choose a feature tree or palm for the centre of the lawn that works with your palette.

Along with a new coat of paint on the timber of the house, you could achieve a wonderful new look in a cost effective way.

All the best!